Spring cushion construction



April 30, 1963 H. c. FLINT 3,087,719

spams CUSHION CONSTRUCTION Filed May 23, 1960 '7 Sheets-Sheo 1 IN V ENTOR.

April 30, 1963 H. c. FLINT 3,0

SPRING CUSHION CONSTRUCTION Filed May 23, 1960 7 Sheets-Sheet 2 IN VENTOR. fly/dz z 6. 21 277? April 30, 1963 H. c. FLINT 3,087,719

SPRING CUSHION CONSTRUCTION Filed May 23, 1960 7 Sheets$heet 3 INVENTOR.@7472] 6'. 777

April 30, 1963 H. c. FLINT 3,087,719

SPRING CUSHION CONSTRUCTION Filed May 23, 1960 7 Sheets-Sheet 4 \j 1 NWWW W WW y G n mm :U n n w w April 30, 1963 H. c. FLINT 3,087,719

SPRING CUSHION CONSTRUCTION Filed May 23, 1960 7 Sheets-Sheet 5INVENTOR. f/y/awi C. FZ'zrz.

April 30, 1963 H. c. FLINT 3,087,719

SPRING CUSHION CONSTRUCTION Filed May 23, 1960 7 Sheets-Sheet 6INVENTOR. @22 7! 61771372? fiw 2M A ril 30, 1963 SPRING CUSHIONCONSTRUCTION Filed May 23, 1960 '7 Sheets-Sheet '7 INVENTOR.

H. c. FLINT 3,087,719 I United States Patent 3,087,719 SPRING CUSHIONCONSTRUCTION Hyland C. Flint, Novi, Mich., assignor to American MetalProducts Company, Detroit, Mich., a corporation of Michigan Filed May23, 1960, Ser. No. 31,029 24 Claims. (Cl. 26785) This invention relatesto spring elements of double unit construction, and particularly to aspring element having a main load supporting portion and a helperportion disposed adjacent thereto.

In the patent to H. C. Flint, No. 2,868,276, a spring cushion isillustrated having main load bearing spring strips .interspersed withhelper spring strips disposed therebetween which are constructedindependently of each other. The separate units in this constructionresulted in the use of an increasing number of attaching elements forthe cushion even though either or both of the elements are made ofsubstantially straight wire. While straight wire elements reduce thelength of wire employed, it was found that to provide softness the endsof the straight sections must have coil springs, rubber blocks, loops,reversely bent sections and the like applied thereto. The provision ofthe flexibility near the ends of the elements did not produce assatisfactory a result as when the flexibility or yield point is disposedadjacent to the A point of the load bearing area which is approximatelyone-third the length of the load bearing portion of the spring strip asmeasured forwardly from the rear edge. To this end torsion bars arepreferably provided in both of the elements between the ends thereof. Tomaintain the flexibility and the desired support at the point where themain load is applied, that is to say, at the A point, it was founddesirable to control the deflection and contouring of the load bearingarea, and this was successfully accomplished by the use of a brace rodextending from the lower supporting element at the rear of the unit tothe forward portion of the main load bearing section. By connecting thehelper portion of the spring unit of the present invention at its rearend to the rear end of the load bearing section and so form the end asto permit it to pivot, the same effect is produced in the main loadbearing section of the spring unit, thereby eliminating the brace rod,which adds further to the simplicity and usefulness of the presentdouble section construction.

The high-low sections of the spring unit have the advantage of providinga desirable contour to the support for a light as well as a heavyperson, the support for the latter being substantially assisted by thelower or helper section which is located between the high or main loadbearing section. The main load bearing section is so constructed as topermit the rear end to have a high degree of vertical flexibility toavoid building up pressure at the base of the spine of a seated person.This is accomplished by a 360 turn of the last loop at the rear of theload bearing section, and two additional 90 turns carry the wire to apivot point on the rear rail. The wire sections disposed on the axis inthe pivot point are then bent at another 90 angle and continuedforwardly and formed into the lower helper section of the spring at theside of the main load bearing section thereof. The axle section joiningthe two units is freely pivoted in the supporting clips on the rearframe member and the need for the brace rod mentioned above, asdisclosed in the H. C. Flint Patent 2,719,578, is eliminated.

When additional strength is desired in the spring units, instead ofincreasing the gauge of the wire thereof, stop elements are provided onthe frame to engage an arm on either or both of the sections of the unitat the front or rear of the frame member to prevent the rotation of thesupporting ends, which thereby substantially strengthens the loadbearing section and the helper section from defleeting. This is mostdesirable for the end springs of the assembled cushion and also at thecentral tunnel portion of the floor, if such a tunnel portion isemployed. When the brace rod was used in the manner as illustrated inthe drawings of the mentioned patent, the amount the rear end of theunit could pivot was limited and the Z-shaped rear supporting portion ofthe load bearing surface was restricted also in vertical flexibility.Such restrictions are eliminated in the present spring unit and the rearend may move vertically to the degree as required by the load even tothe extent of portions of the load bearing section passing downwardlybeyond portions of the helper section or the axle portion of the wirejoining the two sections together. The thickness of the resulting seatis substantially reduced, accomplished by the reduction in height of theend supporting portions and the directing of the joining sectionsdownwardly before being extended forwardly adjacent to the main loadbearing section.

When load is applied to the A point of the load hearing sections of aspring unit, the downward movement of the surface causes the pivotedportions or axle which joins the two sections to transfer a load to thehelper section, thereby causing its surface to begin to lower but at aslower rate than the deflection of the main load bearing section whichhas a softer construction. In practice, this ratio of vertical travel atthe A point shows that the upper surface will move downwardly about 2 /2before the applied load contacts the lower section and that before thiscontact occurs the lower section will have moved downwardly aboutThereafter, both sections support the load and move downwardly togetheruntil a pre determined static load point is reached which determines thelocation of the eye level of the occupant. It will thus be seen that thehigher surface of the load bearing section moves substantially fasterthan the lower surface of the helper section. This is due to the highlyflexible rear end of the load bearing section and the larger Vsupporting portion at the front end thereof in contrast to the helpersection which has only limited flexibility at the rear end and a muchsmaller V supporting portion at its front end.

As more and more of the load is applied to the load bearing section ofthe unit, the lower helper section slowly deflects until the deflectionof the load bearing section catches up with that of the helper sectionwhich begins to pick up load so that both sections operate in unisonthereafter to support the load with a maximum degree of comfort. Byemploying V-shaped supporting portions at the front ends of the loadbearing and helper sections, the front border wire connecting the pointof juncture of the V supports with the load bearing sections appearssubstantially softer to a person of light weight than would occur ifeach section, rather than alternate sections, were attached to theborder wire. This will also be true of a heavy person, with the softnessbeing maintained when the front end of the load bearing sections isdeflected into the plane of the V supports for the helper sections.Therefore, it was found that there is no necessity for interconnectingthe V supporting portions of the helper section of the unit and thatsuch portions were sufiiciently stabilized by contact with the seat padwhen applied lthereover. This arrangemtnt eliminates substantial cost,time, labor and material.

The unit having the joined load bearing and helper sections providessubstantial flexibility for the construction of cushions. The same unitmay be employed over the entire seating area with the one end areahaving the helper section omitted, or right and left-hand units may beemployed, with the two helper sections being adjacent the center of theframe. It is within the purview of the invention to have the pluralityof the units constructed continuously so as to have an entire framespanned by the connected units to eliminate handling of the separateunits and the difiiculty of untangling a plurality of the units.

Accordingly, the main objects of the invention are: to provide a springunit of two joined sections, one a load supporting section and the othera helper section disposed adjacent thereto; to join a load bearing andhelper section of a spring unit with a pivotal bar at their rear ends bywhich the rear ends of the composite unit are pivotally supported on therear frame element of a cushion; to form a cushion of composite loadbearing and helper sections which are of the same hand and which extendacross the frame, with the helper section at one end omitted therefrom;to form a spring cushion from composite units of joined load bearing andhelper sections of the right and left-hand type, with the helpersections disposed adjacent to each other at the center of the frame orspaced apart with a single spring unit disposed therebetween; to form aspring cushion from a plurality of composite units made up of a loadbearing and helper section which are joined together in continuousconstruction and which are directly applied to a frame to eliminate thehandling, tangling and individual application of the units thereto; toprovide a more rugged spring unit at substantially reduced cost, and, ingeneral, to construct a spring cushion from units which are simple inconstruction and economical of manufacture and assembly.

Other objects and features of novelty of the invention will bespecifically pointed out or will become apparent when referring, for abetter understanding of the invention, to the following descriptiontaken in conjunction with the accompanying drawings, wherein:

FIGURE 1 is a plan view of a seat cushion constructed on a frame fromspring units, embodying'features of the present invention;

FIG. 2 is an enlarged end view of the structure illustrated in FIG. 1,as viewed from. the line 22 thereof;

FIG. 3 is a plan view of the spring unit illustrated in FIG. 1;

FIG. 4 is a view in elevation of the spring unit illustrated in FIG. 3;

FIG. 5 is a plan view of a seat cushion construction, similar to thatillustrated in FIG. 1, showing another form thereof;

FIG. 6 is an enlarged sectional view of the structure illustrated inFIG. 5, taken on the line 66 thereof;

FIG. 7 is a view of structure, similar to that illustrated in FIG. 5,showing a still further form of the invention;

FIG. 8 is an enlarged sectional view of the structure illustrated inFIG. 7, taken on the line 8-8 thereof;

FIG. 9 is a broken plan view of a seat cushion, similar to thatillustrated in FIG. 7, showing a still further form of the invention;

FIG. 10 is an enlarged sectional view of the structure illustrated inFIG. 9, taken on the line 1010 thereof;

FIG. 11 is a view of a spring unit, similar to that illustrated in FIG.3, showing another form thereof;

FIG. 12 is a view in elevation of the spring unit illustrated in FIG.11;

FIG. 13 is a broken view of a spring unit, similar to that illustratedin FIGS. 3 and 11, showing a further form of construction thereof;

FIG. 14 is a plan view of a spring unit, similar to that illustrated inFIG. 11, showing still another form which the unit may assume, and

FIG. 15 is a view in elevation of the spring unit illustrated in FIG.14.

In FIGURES l to 4, a seat cushion 21 is illustrated as being constructedon a frame 22 from composite spring units 23 and 24. The spring units 23and 24 are of the same construction except that of being of the oppositehand. The units are constructed to have a load bearing section 25 and ahelper section 26 which are joined together at the rear end by a lengthof wire 27 which forms an axle by which the rear end is supported in oneor a pair of clips 28 for pivotal movement therein. The load hear,- ingsection 25 is formed back and forth to provide oppositely facing loops29 and 30 with a V-shaped supporting portion 31 at the front end. Theloops may be of the same or varying dimensions to control the contourassumed by the load bearing section 25 when a load is applied thereto.Such a load-bearing section may follow the construction of the springstrips of the H. C. Flint et al. Patent No. 2,684,844 on formed wire. Atthe rear end 32 of the load bearing area, the wire is formed forwardlyand downwardly at 33, transversely at 34, and rearwardly and downwardlyat '35 to join with the axle portion 27 which is connected to the helpersection 26 of the unit. The helper section is disposed alongside of andspaced from the load bearing section. The helper section has loops 36and 37 which are oppositely facing and of ditferent width for thepurpose of regulating the strength of the section.

The forward end of the load bearing section has a supporting portion 38of V shape containing oppositely disposed loops 39 and 41 in the upperand lower arms thereof. The lower arm has the end formed into a U-shaped element 42, the transverse end 43 of which is secured on top ofthe front frame member 44 by a clip 45 which retains the end againstdownward pivotal movement. A similar supporting portion 46 but ofsubstantially less height is provided at the forward end of the helpersection of the unit, with its lower arm provided with a U-shaped element42 having a transverse end 43 which rests upon the frame element 44 andis secured thereon by a clip 45'. The spring units 23 and '24- areexactly the same as pointed out hereinabove except for the helpersections 26 being located on the left or right-hand side of the loadbearing section 25 of the unit.

InFIG. 1, the'units 23 on the left of the frame 22 can be said to beright-handed, while the units 24 on the right thereof can be said to beleft-handed. With this arrangement, the helper sections 26 of both unitsare disposed adjacent to each other on the center line of the frame. AU-shaped border wire 47 extends along the sides and across the front ofthe spring units, being secured by bands 48 to the forward ends of theload bearing sections 25 above and forwardly of the forward end of thehelper sections 26. The arch or spanning units 49 are secured to theside portions of the border wire 47 and to portions of the end loadbearing sections 25 of the end units, with nifset ends 51 extending intoapertures '52 in the rear frame element 53, as more clearly illustratedin FIG. 6.

In FIG. 5, the units 23 of right-hand construction are illustrated asbeing joined together to form the entire spring supporting portion ofthe cushion, with all of the units constructed from a continuous lengthof wire. The right-hand helper section 26 is removed from the assembly,leaving the right-hand end unit a load bearing section 25'. It iscontemplated that the same type of forming dies will be utilized forconstructing the continuous wire spring surface of FIG. 5 as is employedin making the single units 23 of FIG. 1. It will be only necessary tomove the joining section 27 outwardly as the corners are formed by abend at the punction with the prior formed unit and at both ends of thesection 27 and at the forward end of the helper section 26 to fold thesections upon themselves, as illustrated in the figures. As the sectionsare folded and moved rearwardly with the sections already folded,another length of wire to be formed is drawn through straighteningelements and the now opened forming dies from a large roll of wireprovided therebeyond. As the folding of the wire occurs, the sectionsalready folded are moved forwardly toward the forming dies and alongtherewith to be in direct continuation of the new sections. After asufficient number of the units have been folded upon themselves in thismanner, ten units as illustrated in FIG. 5, the end helper section 26 iscut from the multiple unit and the multiple unit is advanced over a seatframe which is raised to have open clips 28 thereon receive the joiningor axle portions 27 at the rear and the transverse ends 43 at the frontby open clips 45. The clips are bent over to secure the axles 27 andends 43 by adjacent clinching tools which are automatically operated tohave the continuous unit supported directly on the frame without anyhandling and with the elimination of tangling as often occurs. After oneor more pairs of a section are formed for the next multiple unitassembly, the helper section cut from the prior multiple unit is cutfrom the forward end of the multiple unit being formed. The frame withthe multiple unit thereon is advanced through a normalizing furnace anda paint spray booth before or preferably after the border wire 47 andspanning units 49 are applied thereto.

In FIGS. 7 and 8, a central section of the frame is illustrated which isof exactly the same construction as that illustrated in FIG. 1, with theexception that the adjacent helper sections 26 of the spring units 23and 24 at the center of the frame are spaced a substantial distanceapart to uncover a tunnel area in the floor of the vehicle. In thetunnel area spring units 54 are employed having the U-shaped ends 42secured rigidly on a ledge 55 of the frame 53 by a tunnel element 56 andan upstanding retaining flange 57 in the conventional manner. Theopposite end of the spring units 54 contains a V supporting section 59having a U-sh-aped supporting end 42 thereon which is secured in thetunnel element '56. The spring units 54 are more or less of a standardtype, being made from formed wire to have oppositely disposed loops 61and 62 in the load bearing portion, the forward ends of which aresecured to the border wire 47 by the bands 48.

In FIGS. 9 and 10, a still further form. of the invention isillustrated, that wherein the seat cushion structure 21 has beenmodified to have the central spring units 23 and 24 spaced apartsufficiently to have a single sprlng element 63 disposed on the centerline of the frame between the helper sections 26 of the units. Thespring element 63 has a load bearing section 64, a V-shaped supportingsection 65 at the front end, and a V-shaped supporting section 66 at therear end. A brace rod 67 interconnects the apex of the rear V section 66to the load bearing section 64 near the forward end thereof, beingsecured in position by a clamping band 48. The spring follows thecontour of the load bearing sections 25 of the units 23 and 24 at thecenter of the frame.

In FIGS. 11 and 12, a still further form of spring unit is illustrated,that wherein the load bearing section 71 is formed of oppositelydisposed loops 72 and 73 and a coiled rear end 74 joined to the pivotedaxle portion 75. The axle portion is connected to a helper section 76having oppositely disposed loops 77 and 78 of dilferent lengths and anextending end 79 which is disposed over a corner of a loop 81 andsecured in position by a hook 82. The forward end 83 of the load bearingsection has a downwardly extending V-shaped portion 84 which is securedto the frame 85 by a tunnel element 86 and retaining flange 87. The axleportion 75 of the unit is supported in a pair of clips 88 for pivotalmovement therein on the rear frame element 89.

In view of the substantial length of wire required to construct any ofthe units 23, 24 and 71, it is within the purview of the invention toconstruct the load bearing and helper sections independently of eachother and have the rear ends rigidly joined to form the axle portionbetween the sections. Such an arrangement is illustrated in FIG. 13wherein the axle portion 91 on the helper section 26 is extended atright angles at 92 and further flanged at 93, with the pivoted end 94 ofthe load bearing section 25 similarly bent to provide a right angleportion 92 and a bent end 93. A band 48 connects the right angleportions 92 in fixed relation to each other, retained in position by thebent ends 93. The rear ends 91 and 94 of both sections will pivot inunison in the same manner as when the single axle portion 27 was acontinuous length of wire supported in the clips 28.

A further form of composite spring unit is illustrated in FIGS. 14 and15 wherein the load bearing section 95 of the unit has a helper section96 connected thereto by a section of Wire 97 which is supported forpivotal movement in the clips 28 in the manner as pointed outhereinabove. The load bearing section has a straight portion 98forwardly of the A point thereof which terminates in a loop 99 which issecured to a border wire 101 by a band 48. The front end of the loadbearing section 95 has a V portion 102 extending downwardly thereof andprovided with a U-shaped supporting end 42 having the transverse endportion 43 secured in a tunnel element 45 and retained in position by anupwardly extending flange 103. RearWa-rdly of the straight portion 98 ofthe load bearing section of the unit, oppositely disposed loops 104 and105 are provided which terminate in *a V end section 106 which is joinedby the pivoted axle portion 97 to the helper section 96 which has adownwardly extending portion 107, a forwardly extending portion 108, atransverse portion 109 and a forwardly extending portion 111. Theforward end of the extending portion 111 is disposed over a torsion bar112 of the front V supporting element 102 and beneath the torsion bar113 forwardly thereof. A hooked end portion 114 on the forwardlyextending straight portion 111 extends upwardly over the torsion bar 113to anchor the end to the apex portion of the front V supporting portion102. It will be noted that the end torsion bar 115 of the load bearingsection 95 is narrower than the portions 108 and 116 with which thetorsion bar 115 might otherwise engage when deflected. In all of thespring constructions, the rear end of the load bearing section is softso that it may deflect a substantial amount when loaded without havingthe rearmost torsion bar contact the rear V-shaped supporting elementsof both the load bearing and helper sections which are constructed ofgreater Width so as to be out of engagement therewith.

The spring cushion constructed from the composite units providessubstantial durability and comfort at a substantial saving of time andmoney. Heretofo-re, when greater support was desired at each side edgeof the cushion or in the area about the tunnel at the center of thecushion, heavier gauge wire was employed which added further to thedifficulty of separating the springs and having them disposed atdifferent points along the frame. In the present arrangement, theendrnost spring units are mounted higher on the supporting frame, asillustrated in FIG. 2. The end portion 121 of the end section 25 ispivotally supported in clips 28 and abuts the outwardly extendingbracket 123 attached to the inner face of the rear frame element 53. Bymounting the rear end of the load bearing section 25 higher, pull-downheight is provided which tensions the cover material applied over theface of the cushion in the conventional manner. The presence of thebracket 123 prevents the rotation of the end portion 121 downwardly,thereby resisting the downward deflection of the load bearing sectionwhich therefore is able to support a substantially greater load. It willbe further noted that a bracket 124 is provided forwardly of the face ofthe rear frame element 53 in position to engage an arm 122 of the loadbearing section of the spring which is adjacent to the tunnel or at someother point along the frame to strengthen one or more of the springsections at that point. It is to be understood that the bracket 124 mayintercept the arm 122 of the load bearing section or an arm on thehelper section, or both, depending upon the amount of strength requiredin the spring sections. Thus, the entire cushion may be made from thesame gauge wire and the same unit structure while strengthening certainof the spring sections by controlling the degree of pivotal movement ofthe joining axle portion of the spring units.

This makes possible the construction of the entire spring area of theframe from a single, continuous wire and the controlling of thesupporting strength of each of the units thereof at any point along theframe. It Was found that in a bucket seat type of construction, whenemploying the bracket 123 on the right and left-hand load bearingsections, the sections were retained elevated above the inner sectionswhich were capable of deflecting a substantial amount below the sidesections which encompassed the occupant. Therefore, the usefulness ofthe brackets 123 and 124 is not limited to the example illustratedsince, as pointed out with regard to the tunnel area and the bucketseat, there are many applications where it is desired to add strength atcertain points of the cushion surface. The restricted pivoting at therear of the load bearing section of the spring units and in someinstance of the helper sections thereof will have substantial bearing onstrengthening areas of the cushion.

What is claimed is:

1. In a seat construction, a seat frame having front and rear membersspaced by side members, a plurality of spring strips extending betweensaid front and rear members, and means for securing the front and rearends of each strip to the front and rear frame members in alignedrelation along the length thereof, said spring strips being made from acontinuous length of wire.

2. In a seat construction, a seat frame having front and rear membersspaced by side members, a plurality of spring strips extending betweensaid front and rear members having downwardly extending front endsupporting portions of different heights, and means securing the frontand rear ends of the spring strips to said frame members in alignedrelation along the length thereof, the sidemost spring strips andcertain of the medial spring strips having the front ends extendingupwardly above other spring strips located therebetween as a result ofthe portions of different heights.

3. In a seat construction, a seat frame having front and rear membersspaced by side members, a plurality of spring strips extending betweensaid front and rear members and with the ends secured thereto in alignedrelation along the length of the members, the sidemost spring strips andcertain of the medial spring strips having the front ends extendingupwardly above other spring strips located therebetween, and a borderwire joining the spring strip having the upwardly extending front endsof greater height.

4. In a seat construction, a seat frame having front and rear membersspaced by side members, a plurality of spring strips extending betweensaid front and rear members and with the ends secured thereto in alignedrelation along the length of the members, the sidemost spring strips andcertain of the medial spring strips having the front ends extendingupwardly above other spring strips located therebetween, and a borderwire joining the spring strip 'having the upwardly extending front endsof greater height, the rear ends of the sidemost spring strips beingsupported higher than spring strips disposed therebetween.

5. In a seat construction, a seat frame having front and rear membersspaced by side members, and a plurality of spring strips extendingbetween said front and rear members, the ends of each spring strip beingsecured to the front and rear frame members in aligned relation alongthe length thereof, the adjacent pairs of said spring strips beingjoined together at the rear end.

6. In a seat construction, a seat frame having front and rear membersspaced by side members, and a plurality of spring strips extendingbetween said front and rear members with the ends of each spring stripsecured thereto, the adjacent pairs of said spring strips being joinedtogether at the rear end, the front end of one spring strip of saidpairs being lower than the front end of the other spring strip.

7. In a seat construction, a seat frame having front and rear membersspaced by side members, and a plurality of spring strips extendingbetween said front and rear members and secured thereto, the adjacentpairs of said spring strips being joined together at the rear end, thefront end of one spring strip of said pairs being lower than the frontend of the other spring strip, the spring strip at the left side and atthe right side of the frame being the one having the greater height atthe front.

8. In a seat construction, a seat frame having front and rear membersspaced by side members, and a plurality of spring strips extendingbetween said front and rear members and secured thereto, the adjacentpairs of said spring strips being joined together at the rear end, thefront end of one spring strip of said pairs being lower than the frontend of the other spring strip, the spring strip at the left side and atthe right side of the frame being the one having the greater height atthe front, the adjacent spring strips of the pair at the center of theframe being the ones of lesser height at the front.

9. In a seat construction, a seat frame having front and rear membersspaced by side members, and a plurality of spring strips extendingbetween said front and rear members and secured thereto, the adjacentpairs of said spring strips being joined together at the rear end, thefront end of one spring strip of said pairs being lower than the frontend of the other spring strip, the endmost spring strips and certain ofthose therebetween having front edges of greater height than springstrips disposed therebetween.

10. In a seat construction, a seat frame having front and rear membersspaced by side members, a plurality of spring strips extending betweensaid front and rear members and secured thereto, the adjacent pairs ofsaid spring strips being joined together at the rear end, the front endof one spring strip of said pairs being lower than the front end of theother spring strip, the spring strip at the left side and at the rightside of the frame being the one having the greater height at the front,the adjacent spring strips of the pair at the center of the frame beingthe ones of lesser height at the front, the adjacent spring strips beingspaced apart, and a spring strip having its front end of greater heightdisposed therebetween.

11. In a seat construction, a seat frame having front and rear membersspaced by side members, a plurality of spring strips extending betweensaid front and rear members and secured thereto, said spring stripsbeing made up into pairs of sections, and a load bearing section joinedto an adjacent helper section, the front end of the latter section beinglower than the front end of the former section.

12. In a seat construction, a seat frame having front and rear membersspaced by side members, a plurality of spring strips extending betweensaid front and rear members and secured thereto, said spring stripsbeing made up into pairs of sections, and a load bearing section joinedto an adjacent helper section, the front end of the latter section beinglower than the front end of the former section, said two sections beingjoined at the rear end providing a straight portion by which the twosections are supported for pivotal movement on said frame.

13. In a spring unit for a seat frame, a load bearing section made ofwire bent back and forth to form a seating area having a downwardlyextending front supporting portion and a downwardly extending rearsupporting portion the end of which is extended laterally and joined toa helper section disposed adjacent to the load bearing section.

14. In a spring unit for a seat frame, a load bearing section made ofwire bent back and forth to form a seating area having a downwardlyextending front supporting portion and a downwardly extending rearsupporting portion the end of which is extended laterally and joined toa helper section disposed adjacent to the load bearing section, andmeans for supporting the laterally extending end portion of the unit toa frame for pivotal movement relative thereto.

15. In a spring unit for a seat frame, a load bearing section made ofwire bent back and forth to form a seating area having a downwardlyextending front supporting portion and a downwardly extending rearsupporting portion the end of which is extended laterally and joined toa helper section disposed adjacent to the load bearing section, meansfor supporting the laterally extending end portion of the unit to aframe for pivotal movement relative thereto, and a bracket in engagementwith said rear supporting portion for strengthening the load bearingsection of the spring unit.

16. In a spring unit for a seat construction, a load bearing sectionhaving oppositely disposed loops and downwardly extending supportingportions at the front and rear, the rear supporting portions extendinglaterally and joined to the rear end of an adjacent helper section whichhas a downwardly extending supporting portion at the front end of lessheight than the height of the supporting portion of the front end of theload supporting section.

17. In a spring unit for a seat construction, a load bearing sectionhaving oppositely disposed loops and downwardly extending supportingportions at the front and rear, the rear supporting portions extendinglaterally and joined to the rear end of an adjacent helper section whichhas a downwardly extending supporting portion at the front end of lessheight than the height of the supporting portion of the front end of theload supporting section, and pivot means on the frame for supporting thelaterally extending portion which transfers a load on the load bearingsection to the helper section which deflects at a slower rate whilestrengthening the former section at an increasing rate until it reachesthe plane of the helper section whereby both sections directly supportthe load.

18. In a spring unit' for a seat construction, a load bearing sectionhaving oppositely disposed loops and downwardly extending supportingportions at the front and rear, the rear supporting portions extendinglaterally and joined to the rear end of an adjacent helper section whichhas a downwardly extending supporting portion at the front end of lessheight than the height of the supporting portion of the front end of theload supporting section, pivot means on the frame for supporting thelaterally extending portion which transfers a load on the load bearingsection to the helper section which deflects at a slower rate whilestrengthening the former section at an increasing rate until it reachesthe plane of the helper section whereby both sections directly supportthe load, and a bracket on the frame engageable with the rear portion ofone of the sections for the purpose of strengthening the section forsupporting a load.

19. In a spring unit, a load bearing section containing oppositelydisposed loops and a downwardly extending front and rear supportingportion by which the load bearing section is supported on a frame, theend of the down- 10 wardly extending rear supporting portion beingextended laterally and projected forwardly to widen the unit and form ahelper section the front end of which is hooked over the front portionof the load bearing section.

20. In a spring construction, a load bearing section having front andrear downwardly disposed supporting portions which are secured to spacedframe elements, the end of the rear supporting portion being extendedlaterally and forwardly with the forward end secured to the downwardlyextending supporting portion at the front end of the load bearingportion.

21. In a spring unit, a load bearing section disposed adjacent to ahelper section having a joining rear portion by which the rear end ofeach section is pivotally supported, and means for securing the joiningrear portions in fixed relation to each other.

22. A spring unit made up of adjacent load bearing and helper sectionswhich are joined together at the forward and rear ends and with theendmost helper section removed between the units so that each unit willhave a load bearing section at each end, a frame upon which theassembled spring unit is disposed, and securing means on said frame forthe ends of said sections.

23. A spring unit made up of adjacent load bearing and helper sectionswhich are joined together at the forward and rear ends and with theendmost helper section removed between the units so that each unit willhave a load bearing section at each end, a frame upon which theassembled spring unit is disposed, securing means on said frame for theends of said sections, a border wire at the sides and forward ends ofthe load bearing sections of the spring unit, and means for securing theborder wire to the forward ends of said load bearing sections.

24. A spring unit made up of adjacent load bearing and helper sectionswhich are joined together at the for- Ward and rear ends and with theendmost helper section removed between the units so that each unit willhave a load bearing section at each end, a frame upon which theassembled spring unit is disposed, securing means on said frame for theends of said sections, a border wire at the sides and forward ends ofthe load bearing sections of the spring unit, and means for securing theborder wire to the forward ends of said load bearing sections, the endsof said border wire being offset and locked in apertures in the frame.

References Cited in the file of this patent UNITED STATES PATENTS1,901,720 Barwinkel Mar. 14, 1933 2,471,777 Reinartz May 31, 1949 2,747,619 Buttner May 29, 1956 2,835,314 Neely May 20, 1958 2,845,996 FlintAug. 5, 1958 2,868,276 Flint Jan. 6, 1959

2. IN A SEAT CONSTRUCTION, A SEAT FRAME HAVING FRONT AND REAR MEMBERSSPACED BY SIDE MEMBERS, A PLURALITY OF SPRING STRIPS EXTENDING BETWEENSAID FRONT AND REAR MEMBERS HAVING DOWNWARDLY EXTENDING FRONT ENDSUPPORTING PORTIONS OF DIFFERENT HEIGHTS, AND MEANS SECURING THE FRONTAND REAR ENDS OF THE SPRING STRIPS TO SAID FRAME MEMBERS IN ALIGNEDRELATION ALONG THE LENGTH THEREOF, THE SIDEMOST SPRING STRIPS ANDCERTAIN OF THE MEDIAL SPRING STRIPS HAVING THE FRONT ENDS EXTENDINGUPWARDLY ABOVE OTHER SPRING STRIPS LOCATED THEREBETWEEN AS A RESULT OFTHE PORTIONS OF DIFFERENT HEIGHTS.